Wireless networks are telecommunications networks that use radio waves to carry information from one node in the network to one or more receiving nodes in the network. Cellular telephony is characterized by the use of radio cells that provide radio coverage for a geographic area, with multiple cells arranged to provide contiguous radio coverage over a larger area. Wired communication can also be used in portions of a wireless network, such as between cells or access points.
Wireless communication technologies are used in connection with many mobile devices, including, for example, satellite communications systems, portable digital assistants (PDAs), laptop computers, and mobile devices (e.g., cellular telephones, user equipment). Such devices can connect to a network (e.g., the Internet) as long as the user is within range of such a wireless communication technology. Mobile devices are assigned an address that serves as a unique identifier within the network.